Transmission power lines have been used for more than a century to transmit power from a generation source to a source of consumption of electric power.
Over time, the transmission lines have been adapted to reduce power consumed by the transmission line itself, particularly in the case of long power lines.
U.S. Pat. No. 7,265,521 B2 discloses a system and approach for minimizing the step voltage change as seen by the utility customer as well as minimizing transients imposed on the fundamental waveform of a normal voltage carried on a utility power network when a reactive power source (e.g., capacitor bank) is instantaneously connected to the utility power. The reactive power source is adapted to transfer reactive power of a first polarity (e.g., capacitive reactive power) to the utility power network. The system includes a reactive power compensation device configured to transfer a variable quantity of reactive power of a second, opposite polarity to the utility power network, and a controller which, in response to the need to connect the shunt reactive power source to the utility power network, activates the reactive power compensation device and, substantially simultaneously, causes the shunt reactive power source to be connected to the utility power.
While the use of reactive power sources as described above do improve the efficiency of a transmission line, the performance of transmission lines would benefit from more improvement, particularly to improve transmission over long transmission lines.